CORNACEAE. 305 



Calyx-tube coherent with the ovary, its limb represented by 4 small teeth at the 

 summit or none. Petals 4, epigynous, valvate in bud. Stamens 4, alternate 

 with the petals. Ovary 2-celled with a single pendulous ovule in each cell; style 

 filiform; stigma simple. Fruit a drupe, the stone 2-celled with 1 seed in each 

 cell. Embryo minute. 



1. CORN US L. Cornel. Dogwood. 

 Flowers greenish or white. (Latin cornu, a horn, on account of the hardness 

 of the wood.) 



Flowers sessile in a head-like cluster with an involucre of 4 to 6 large white petal-like 



bracts; drupe scarlet 1. C. nuttallii. 



Flowers in cymes, inconspicuous: involucre none. 



Leaves lighter colored beneath; drupe white; stone conspicuously channeled on the 



edges 2. C. pubescens. 



Leaves green, alike on both faces, nearly glabrous. 



Stone smooth or somewhat channeled on the edges, not ribbed; drupe whitish or 



bluish 3. C. glabrata. 



Stone channeled on the edges and with 8 filiform longitudinal ribs; drupe blue.... 



4. C. costulata. 



1. C. nuttallii And. Pacific Dogwood. Small tree 10 to 30 ft. high; leaves 

 narrow- or elliptic-obovate or even orbicular, with rounded or shortly acute apex 



3 to 5 in. long, on petioles 2 to 3 lines long; flowers crowded in a head on a 

 thick convex receptacle and surrounded by a conspicuous petal-like involucre; 

 bracts of the involucre commonly 6, white, sometimes tinged with red, obovate 

 to oblong, li/o to 3 in. long, abruptly acute or acuminate; heads % to 1 in. 

 broad, very dense, borne on peduncles 1 to 1^4 in. long; drupe 5 to 6 lines long, 

 scarlet. 



Marin Co. (Erythea, vi, 73), and the Xapa Eange northward to Mt. Shasta, 

 thence southward in the Sierra Nevada; rare in the South Coast Kanges (Mon- 

 terey Co., Santa Cruz Mts.) ; San Diego Co. Inflorescence remarkably beauti- 

 ful, appearing with or before the leaves. Also called Nuttall 's Dogwood and 

 Mountain Dogwood. 



C. canadensis L. Bunch-berry. Herb-like; stem 3 to 6 in. high with a 

 whorl of 6 leaves at summit, a pair of leaves above the middle, and scales 

 below; involucre petal-like. — Mendocino Co. and northward. C. sessilis Torr. 

 Shrub 10 ft. high or more, with yellowish flowers in sessile umbels subtended by 



4 small caducous bracts. — Northern Sierra Nevada west to Trinity Eiver. 



2. C. pubescens Nutt. var. californica C. & E. Creek Dogwood. Shrub 



5 to 15 ft. high with smooth purplish branches and branchlets ; leaves commonly 

 ovate, varying to elliptical, acute, lighter colored and more pubescent, also con- 

 spicuously ribbed, beneath, 2 to 4 in. long; cymes 1% to 2 in. broad; petals 

 oblong, acute, 2 lines long; style glabrous, little or not at all thickened at apex; 

 drupe white, subglobose, 3 lines in diameter ; stone mostly oblique, somewhat 

 flattened, with furrowed edges, each side with 4 less obvious or shallower chan- 

 nels. — (C. californica C. A. Mey.) 



Common on canon stream banks in the Coast Eanges and Sierra Nevada, and 

 along the Sacramento and San Joaquin rivers. Flowering and fruiting from 

 Apr. until Nov. Sterile shoots observed in forest shade at Olema bore leaves 

 to 7 in. long and 5 in. broad. 



3. C. glabrata Benth. Shrub 5 to 12 ft. high, with nearly or quite glabrous 

 twigs; leaves ovate or oblong, acute at each end or often shortly pointed at 

 apex, 1*4 to 2 in. long, green on both faces, obscurely pubescent with short 

 scattered appressed hairs; petioles 3 lines long or less; flowers dull white, many 

 in small cymes; ovary canescent; style slightly pubescent; drupe globose, the 



